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caculate correlation

8 messages · Elham -, Jim Lemon

#
for calculating correlation between?coding and noncoding,first I transposed data?,(rows become columns) so row is control&treatment and columns are gene names.(so I have 2 matrix with same row and different column),I use these function for calculating correlation but all of spearman correlation are NA,why?


control.corr=cor(coding.rpkm[grep("23.C",coding.rpkm$name),-1],ncoding.rpkm[grep("23.C",ncoding.rpkm$name),-1],method= "spearman")






?
tumor.corr=cor(coding.rpkm [grep("27.T", coding.rpkm $name),-1], ncoding.rpkm [grep("27.T", ncoding.rpkm $name),-1],method = "spearman")
#
Hi Elham,
Without knowing much about what coding.rpkm and ncoding.rkpm look
like, it is difficult to say. Have you tried to subset these matrices
as you do in the "cor" function and see what is returned?

Jim

On Tue, Jan 31, 2017 at 6:40 AM, Elham - via R-help
<r-help at r-project.org> wrote:
#
I have 9 experiments control/treatment that I analysed coding and lncoding, after that I normalize expression value.as you know we have different known number of coding and non -coding genes,so for calculating correlation first I transposed data ,(rows become columns)so row is control&treatment and columns are gene names.(so I have 2 matrix with same row and different column).This information is enough? ?
On Tuesday, January 31, 2017 1:06 AM, Jim Lemon <drjimlemon at gmail.com> wrote:
Hi Elham,
Without knowing much about what coding.rpkm and ncoding.rkpm look
like, it is difficult to say. Have you tried to subset these matrices
as you do in the "cor" function and see what is returned?

Jim

On Tue, Jan 31, 2017 at 6:40 AM, Elham - via R-help
<r-help at r-project.org> wrote:

  
  
#
Hi Elham,
This is about the same as your first message. What I meant was, what
do these two expressions return? Is whatever is returned suitable
input for the "cor" function?

coding.rpkm[grep("23.C",coding.rpkm$name),-1]

ncoding.rpkm[grep("23.C",ncoding.rpkm$name),-1]

Jim
On Tue, Jan 31, 2017 at 8:45 AM, Elham - <ed_isfahani at yahoo.com> wrote:
#
this script automatically recognizes what is control among cod and lnc. Note that this script contains a?piece of text that is "grep(".C",cod$name)". This text select - among all column names - those that contain ".C". in my files, I named C1, C2, C3, etc all columns that correspond to controls. In the same manner, I get controls among the lnc, with the text: "grep(".C",lnc$name)"
I`m so sorry,maybe I do not understand you again.
On Tuesday, January 31, 2017 1:27 AM, Jim Lemon <drjimlemon at gmail.com> wrote:
Hi Elham,
This is about the same as your first message. What I meant was, what
do these two expressions return? Is whatever is returned suitable
input for the "cor" function?

coding.rpkm[grep("23.C",coding.rpkm$name),-1]

ncoding.rpkm[grep("23.C",ncoding.rpkm$name),-1]

Jim
On Tue, Jan 31, 2017 at 8:45 AM, Elham - <ed_isfahani at yahoo.com> wrote:

  
  
#
Hi Elham,
What I meant is to simply copy these two expressions into the R command line:

coding.rpkm[grep("23.C",coding.rpkm$name),-1]

ncoding.rpkm[grep("23.C",ncoding.rpkm$name),-1]

and see what comes out. If both return a vector of numbers of the same
length with no NA values, my guess was wrong. If there are NA values,
try adding the argument use=pairwise.complete.obs to the "cor"
statement.

Jim
On Tue, Jan 31, 2017 at 9:17 AM, Elham - <ed_isfahani at yahoo.com> wrote:
#
Hi Dear Jim,

I did it, both return a vector of name of the genes with different?length,as I said before I have list of coding and noncoding so the length are not same.
where is number?!

and at the end of print there is this error :

<0 rows> (or 0-length row.names)
On Tuesday, January 31, 2017 3:07 AM, Jim Lemon <drjimlemon at gmail.com> wrote:
Hi Elham,
What I meant is to simply copy these two expressions into the R command line:

coding.rpkm[grep("23.C",coding.rpkm$name),-1]

ncoding.rpkm[grep("23.C",ncoding.rpkm$name),-1]

and see what comes out. If both return a vector of numbers of the same
length with no NA values, my guess was wrong. If there are NA values,
try adding the argument use=pairwise.complete.obs to the "cor"
statement.

Jim
On Tue, Jan 31, 2017 at 9:17 AM, Elham - <ed_isfahani at yahoo.com> wrote:

  
  
#
Hi Elham,
On Tue, Jan 31, 2017 at 7:28 PM, Elham - <ed_isfahani at yahoo.com> wrote:
Not in the values you are extracting from the data frame. As you are
aware, you can only perform the "cor" operation on numbers. As the
value returned refers to the correlation of _pairs_ of values, the
vectors of numbers should be the same length and there should be some
meaningful relationship between those pairs. Are you just trying to
correlate any old numbers because they are numbers?
This is probably not an error, just R telling you that something that
was requested didn't have anything in it. Maybe one day we will find
out what is in:

coding.rpkm
ncoding.rpkm

and we can provide more informed advice.

Jim